Inflatable rafts are used in a variety of settings, and are sometimes referred to as “inflatable dinghy's,” “rubber dinghy's,” “inflatable rescue boats,” and boats sold under the brand Zodiac®. Some inflatable rafts are “self-bailing” in that they include ports or apertures at various locations that allow for water to enter into, and then be discharged from, the vessel. Inflatable rafts (self-bailing or otherwise) are often constructed with materials such as rubber, polyvinyl chloride, chlorosulfonated polyethylene (CP), para-aramid synthetic fiber (e.g., Kevlar®), and so forth. While inflatable rafts are well-suited for outdoor activities such as fishing, white water rafting (for which self-bailing rafts are particularly suitable), etc., they are less suited for a variety of other applications, particularly rescue-related activities, for various reasons.
In swift water rescues (e.g., caused by flash floods, dam/levy failures, etc.), a water vessel may be launched upstream from individuals in need of rescue and allowed to drift downstream towards the endangered individuals. In most cases a rope or cable (“rigging line”) may be secured to the vessel's bow (e.g., using a D-ring or other similar hardware) from the launch point, so that the bow (or simply one side of a symmetric raft) remains pointed upstream as the current carries the vessel downstream. If a conventional self-bailing inflatable raft is used in such a scenario, the downstream current (which may be moving downstream faster than the raft) may cause the raft to take on water so quickly that its self-bailing mechanisms are unable to keep up, causing the raft to sink or be swamped. In particular, fore self-bailing ports (i.e. ports towards the front of the raft) may take on water more quickly than aft ejection ports towards the raft's stern are able to discharge the water. In some cases, inflow from fore self-bailing ports may exceed 10-12 cubic feet of water. This may cause excessive force to be applied to the rigging line and/or to anchors on the raft to which the rigging line is secured.
Additionally, in swift water rescues and/or in other rescue scenarios, such as floods, there may be substantial debris, or “top load,” at or near the surface of the water that can damage an inflatable raft. Additionally, in flood situations, various objects such as street signs, mailboxes, fences, vehicles, etc., may be submerged and thus not visible to passengers of a vessel. These unseen objects are capable of causing significant damage to, and potentially sinking, an inflatable raft.